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      <h1 id="MyBatis-配置解析"><a href="#MyBatis-配置解析" class="headerlink" title="MyBatis 配置解析"></a>MyBatis 配置解析</h1><h2 id="核心配置文件"><a href="#核心配置文件" class="headerlink" title="核心配置文件"></a>核心配置文件</h2><ul>
<li>mybatis-config.xml 系统核心配置文件</li>
<li>MyBatis 的配置文件包含了会深深影响 MyBatis 行为的设置和属性信息</li>
<li>能配置的内容如下：</li>
</ul>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br></pre></td><td class="code"><pre><span class="line">configuration（配置）</span><br><span class="line">    properties（属性）</span><br><span class="line">    settings（设置）</span><br><span class="line">    typeAliases（类型别名）</span><br><span class="line">    typeHandlers（类型处理器）</span><br><span class="line">    objectFactory（对象工厂）</span><br><span class="line">    plugins（插件）</span><br><span class="line">    environments（环境配置）</span><br><span class="line">        environment（环境变量）</span><br><span class="line">            transactionManager（事务管理器）</span><br><span class="line">            dataSource（数据源）</span><br><span class="line">    databaseIdProvider（数据库厂商标识）</span><br><span class="line">    mappers（映射器）</span><br><span class="line"><span class="comment">&lt;!-- 注意元素节点的顺序！顺序不对会报错 --&gt;</span></span><br></pre></td></tr></table></figure>



<p>可以阅读 mybatis-config.xml 上面的dtd的头文件！</p>
<a id="more"></a>

<h2 id="1-environments元素"><a href="#1-environments元素" class="headerlink" title="1. environments元素"></a>1. environments元素</h2><ul>
<li><p>MyBatis 可以配置成适应多种环境，这种机制有助于将 SQL 映射应用于多种数据库之中</p>
</li>
<li><p><strong>不过要记住：尽管可以配置多个环境，但每个 SqlSessionFactory 实例只能选择一种环境。</strong></p>
</li>
<li><p>配置MyBatis的多套运行环境，将SQL映射到多个不同的数据库上，必须指定其中一个为默认运行环境（通过default指定）</p>
</li>
</ul>
<p>标准定义如下：</p>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">environments</span> <span class="attr">default</span>=<span class="string">"development"</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">environment</span> <span class="attr">id</span>=<span class="string">"development"</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">transactionManager</span> <span class="attr">type</span>=<span class="string">"JDBC"</span>&gt;</span></span><br><span class="line">      <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"..."</span> <span class="attr">value</span>=<span class="string">"..."</span>/&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">transactionManager</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">dataSource</span> <span class="attr">type</span>=<span class="string">"POOLED"</span>&gt;</span></span><br><span class="line">      <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"driver"</span> <span class="attr">value</span>=<span class="string">"$&#123;driver&#125;"</span>/&gt;</span></span><br><span class="line">      <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"url"</span> <span class="attr">value</span>=<span class="string">"$&#123;url&#125;"</span>/&gt;</span></span><br><span class="line">      <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"username"</span> <span class="attr">value</span>=<span class="string">"$&#123;username&#125;"</span>/&gt;</span></span><br><span class="line">      <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"password"</span> <span class="attr">value</span>=<span class="string">"$&#123;password&#125;"</span>/&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">dataSource</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;/<span class="name">environment</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">environments</span>&gt;</span></span><br></pre></td></tr></table></figure>



<h3 id="子元素节点-事物管理器（transactionManager）"><a href="#子元素节点-事物管理器（transactionManager）" class="headerlink" title="子元素节点 事物管理器（transactionManager）"></a>子元素节点 事物管理器（transactionManager）</h3><p>在 MyBatis 中有两种类型的事务管理器（也就是 type=”[JDBC|MANAGED]”）：</p>
<ul>
<li>JDBC – 这个配置就是直接使用了 JDBC 的提交和回滚设置，它依赖于从数据源得到的连接来管理事务作用域。</li>
<li>MANAGED – 这个配置几乎没做什么。它从来不提交或回滚一个连接，而是让容器来管理事务的整个生命周期（比如 JEE 应用服务器的上下文）。 默认情况下它会关闭连接，然而一些容器并不希望这样，因此需要将 closeConnection 属性设置为 false 来阻止它默认的关闭行为。例如:</li>
</ul>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">transactionManager</span> <span class="attr">type</span>=<span class="string">"MANAGED"</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"closeConnection"</span> <span class="attr">value</span>=<span class="string">"false"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">transactionManager</span>&gt;</span></span><br></pre></td></tr></table></figure>

<p>​    <strong>提示</strong>: 如果你正在使用 Spring + MyBatis，则没有必要配置事务管理器， 因为 Spring 模块会使用自带的管理器来覆盖前面的配置。</p>
<ul>
<li>详情：<a href="http://www.mybatis.org/mybatis-3/zh/configuration.html#environments" target="_blank" rel="noopener">点击查看官方文档</a></li>
</ul>
<h3 id="子元素节点-数据源（dataSource）"><a href="#子元素节点-数据源（dataSource）" class="headerlink" title="子元素节点 数据源（dataSource）"></a>子元素节点 <strong>数据源（dataSource）</strong></h3><ul>
<li><p>作用：连接数据库 –&gt;dataSource 元素使用标准的 JDBC 数据源接口来配置 JDBC 连接对象的资源。</p>
</li>
<li><p>有三种内建的数据源类型       <strong>type=”[UNPOOLED|POOLED|JNDI]”）</strong></p>
<ol>
<li><strong>UNPOOLED</strong>– 这个数据源的实现只是每次被请求时打开和关闭连接。虽然有点慢，但对于在数据库连接可用性方面没有太高要求的简单应用程序来说，是一个很好的选择。 不同的数据库在性能方面的表现也是不一样的，对于某些数据库来说，使用连接池并不重要，这个配置就很适合这种情形。UNPOOLED 类型的数据源具有以下属性。</li>
<li><strong>POOLED</strong>– 这种数据源的实现利用“池”的概念将 JDBC 连接对象组织起来，避免了创建新的连接实例时所必需的初始化和认证时间。 这是一种使得并发 Web 应用快速响应请求的流行处理方式。<strong>(默认的)</strong></li>
<li><strong>JNDI</strong> – 这个数据源的实现是为了能在如 EJB 或应用服务器这类容器中使用，容器可以集中或在外部配置数据源，然后放置一个 JNDI 上下文的引用。这种数据源配置只需要两个属性：</li>
</ol>
</li>
<li><p>数据源也有很多第三方的实现，比如dbcp，c3p0，druid等等….</p>
</li>
</ul>
<h2 id="2-Properties优化"><a href="#2-Properties优化" class="headerlink" title="2.Properties优化"></a>2.Properties优化</h2><p><a href="http://www.mybatis.org/mybatis-3/zh/configuration.html#properties" target="_blank" rel="noopener">官方文档链接</a></p>
<ul>
<li>这些属性都是可外部配置且可动态替换的，既可以在典型的 Java 属性文件中配置，亦可通过 properties 元素的子元素来传递</li>
</ul>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">properties</span> <span class="attr">resource</span>=<span class="string">"org/mybatis/example/config.properties"</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"username"</span> <span class="attr">value</span>=<span class="string">"dev_user"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"password"</span> <span class="attr">value</span>=<span class="string">"F2Fa3!33TYyg"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">properties</span>&gt;</span></span><br></pre></td></tr></table></figure>



<p>如何优化：</p>
<ol>
<li>第一步 ; 在资源目录下新建一个db.properties</li>
</ol>
<figure class="highlight properties"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="attr">driver</span>=<span class="string">com.mysql.jdbc.Driver</span></span><br><span class="line"><span class="attr">url</span>=<span class="string">jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf8</span></span><br><span class="line"><span class="attr">username</span>=<span class="string">root</span></span><br><span class="line"><span class="attr">password</span>=<span class="string">123456</span></span><br></pre></td></tr></table></figure>

<ol start="2">
<li>第二步 : 将文件properties导入到mybatisconfig.xml 配置文件</li>
</ol>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">configuration</span>&gt;</span></span><br><span class="line">    <span class="comment">&lt;!--导入properties文件--&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">properties</span> <span class="attr">resource</span>=<span class="string">"db.properties"</span>/&gt;</span></span><br><span class="line"></span><br><span class="line">    <span class="tag">&lt;<span class="name">environments</span> <span class="attr">default</span>=<span class="string">"development"</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;<span class="name">environment</span> <span class="attr">id</span>=<span class="string">"development"</span>&gt;</span></span><br><span class="line">            <span class="tag">&lt;<span class="name">transactionManager</span> <span class="attr">type</span>=<span class="string">"JDBC"</span>/&gt;</span></span><br><span class="line">            <span class="tag">&lt;<span class="name">dataSource</span> <span class="attr">type</span>=<span class="string">"POOLED"</span>&gt;</span></span><br><span class="line">                <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"driver"</span> <span class="attr">value</span>=<span class="string">"$&#123;driver&#125;"</span>/&gt;</span></span><br><span class="line">                <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"url"</span> <span class="attr">value</span>=<span class="string">"$&#123;url&#125;"</span>/&gt;</span></span><br><span class="line">                <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"username"</span> <span class="attr">value</span>=<span class="string">"$&#123;username&#125;"</span>/&gt;</span></span><br><span class="line">                <span class="tag">&lt;<span class="name">property</span> <span class="attr">name</span>=<span class="string">"password"</span> <span class="attr">value</span>=<span class="string">"$&#123;password&#125;"</span>/&gt;</span></span><br><span class="line">            <span class="tag">&lt;/<span class="name">dataSource</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;/<span class="name">environment</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">environments</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">mappers</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">resource</span>=<span class="string">"mapper/UserMapper.xml"</span>/&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">mappers</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">configuration</span>&gt;</span></span><br></pre></td></tr></table></figure>



<p>注意问题：</p>
<ul>
<li>配置文件优先级问题    【properties优先级高】</li>
<li>新特性：使用占位符</li>
</ul>
<h2 id="3-typeAliases优化"><a href="#3-typeAliases优化" class="headerlink" title="3. typeAliases优化"></a>3. typeAliases优化</h2><ul>
<li>作用：类型别名是为 Java 类型设置一个短的名字。它只和 XML 配置有关，存在的意义仅在于用来减少类完全限定名的冗余。</li>
</ul>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">&lt;!--方式一：--&gt;</span></span><br><span class="line"><span class="comment">&lt;!--配置别名,注意顺序--&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">typeAliases</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Author"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Author"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Blog"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Blog"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Comment"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Comment"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Post"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Post"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Section"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Section"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">typeAlias</span> <span class="attr">alias</span>=<span class="string">"Tag"</span> <span class="attr">type</span>=<span class="string">"domain.blog.Tag"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">typeAliases</span>&gt;</span></span><br></pre></td></tr></table></figure>

<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">&lt;!--方式二：--&gt;</span></span><br><span class="line"><span class="comment">&lt;!--配置别名,注意顺序--&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">typeAliases</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">package</span> <span class="attr">name</span>=<span class="string">"domain.blog"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">typeAliases</span>&gt;</span></span><br></pre></td></tr></table></figure>

<ul>
<li>每一个在包 <code>domain.blog</code> 中的 Java Bean</li>
<li>在没有注解的情况下，会使用 Bean 的<strong>首字母小写</strong>的非限定类名来作为它的别名。</li>
<li>比如 <code>domain.blog.Author</code> 的别名为<code>author</code>；</li>
<li>若有注解，则别名为其注解值。见下面的例子：</li>
</ul>
<figure class="highlight java"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">//注解指定别名</span></span><br><span class="line"><span class="meta">@Alias</span>(<span class="string">"author"</span>)</span><br><span class="line"><span class="keyword">public</span> <span class="class"><span class="keyword">class</span> <span class="title">Author</span> </span>&#123;</span><br><span class="line">    ...</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h2 id="4-设置（settings）"><a href="#4-设置（settings）" class="headerlink" title="4. 设置（settings）"></a>4. 设置（settings）</h2><p><a href="http://www.mybatis.org/mybatis-3/zh/configuration.html#settings" target="_blank" rel="noopener">设置（settings）</a></p>
<p><strong>这是 MyBatis 中极为重要的调整设置，它们会改变 MyBatis 的运行时行为。</strong></p>
<ul>
<li>懒加载  （lazyLoadingEnabled）</li>
<li>日志实现  （logImpl）</li>
<li>缓存开启关闭 （cacheEnabled）</li>
</ul>
<p><strong>一个配置完整的 settings 元素的示例如下：</strong></p>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">settings</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"cacheEnabled"</span> <span class="attr">value</span>=<span class="string">"true"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"lazyLoadingEnabled"</span> <span class="attr">value</span>=<span class="string">"true"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"multipleResultSetsEnabled"</span> <span class="attr">value</span>=<span class="string">"true"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"useColumnLabel"</span> <span class="attr">value</span>=<span class="string">"true"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"useGeneratedKeys"</span> <span class="attr">value</span>=<span class="string">"false"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"autoMappingBehavior"</span> <span class="attr">value</span>=<span class="string">"PARTIAL"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"autoMappingUnknownColumnBehavior"</span> <span class="attr">value</span>=<span class="string">"WARNING"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"defaultExecutorType"</span> <span class="attr">value</span>=<span class="string">"SIMPLE"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"defaultStatementTimeout"</span> <span class="attr">value</span>=<span class="string">"25"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"defaultFetchSize"</span> <span class="attr">value</span>=<span class="string">"100"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"safeRowBoundsEnabled"</span> <span class="attr">value</span>=<span class="string">"false"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"mapUnderscoreToCamelCase"</span> <span class="attr">value</span>=<span class="string">"false"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"localCacheScope"</span> <span class="attr">value</span>=<span class="string">"SESSION"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"jdbcTypeForNull"</span> <span class="attr">value</span>=<span class="string">"OTHER"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">setting</span> <span class="attr">name</span>=<span class="string">"lazyLoadTriggerMethods"</span> <span class="attr">value</span>=<span class="string">"equals,clone,hashCode,toString"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">settings</span>&gt;</span></span><br></pre></td></tr></table></figure>



<h2 id="5-映射器（mappers）"><a href="#5-映射器（mappers）" class="headerlink" title="5. 映射器（mappers）"></a>5. 映射器（mappers）</h2><ul>
<li>映射器 : 定义映射SQL语句文件</li>
<li>首先我们需要告诉 MyBatis 到哪里去找到这些语句。 Java 在自动查找这方面没有提供一个很好的方法，所以最佳的方式是告诉 MyBatis 到哪里去找映射文件。</li>
<li>完全限定资源定位符</li>
</ul>
<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">&lt;!-- 方式一 --&gt;</span></span><br><span class="line"><span class="comment">&lt;!-- 使用相对于类路径的资源引用 --&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">mappers</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">resource</span>=<span class="string">"org/mybatis/builder/AuthorMapper.xml"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">resource</span>=<span class="string">"org/mybatis/builder/BlogMapper.xml"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">resource</span>=<span class="string">"org/mybatis/builder/PostMapper.xml"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">mappers</span>&gt;</span></span><br></pre></td></tr></table></figure>

<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">&lt;!-- 方式二 --&gt;</span></span><br><span class="line"><span class="comment">&lt;!-- 使用映射器接口实现类的完全限定类名</span></span><br><span class="line"><span class="comment">	需要配置文件名称和接口名称一致，并且位于同一目录下 --&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">mappers</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">class</span>=<span class="string">"org.mybatis.builder.AuthorMapper"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">class</span>=<span class="string">"org.mybatis.builder.BlogMapper"</span>/&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">mapper</span> <span class="attr">class</span>=<span class="string">"org.mybatis.builder.PostMapper"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">mappers</span>&gt;</span></span><br></pre></td></tr></table></figure>

<figure class="highlight xml"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">&lt;!-- 方式三 --&gt;</span></span><br><span class="line"><span class="comment">&lt;!-- 将包内的映射器接口实现全部注册为映射器</span></span><br><span class="line"><span class="comment">但是需要配置文件名称和接口名称一致，并且位于同一目录下 --&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">mappers</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">package</span> <span class="attr">name</span>=<span class="string">"org.mybatis.builder"</span>/&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">mappers</span>&gt;</span></span><br></pre></td></tr></table></figure>


      
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                <!-- element will get class pswp__preloader--active when preloader is running -->
                <div class="pswp__preloader">
                    <div class="pswp__preloader__icn">
                        <div class="pswp__preloader__cut">
                            <div class="pswp__preloader__donut"></div>
                        </div>
                    </div>
                </div>
            </div>

            <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap">
                <div class="pswp__share-tooltip"></div>
            </div>

            <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)">
            </button>

            <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)">
            </button>

            <div class="pswp__caption">
                <div class="pswp__caption__center"></div>
            </div>

        </div>

    </div>

</div>

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/photoswipe@4.1.3/dist/photoswipe.min.css">
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/photoswipe@4.1.3/dist/default-skin/default-skin.css">
<script src="https://cdn.jsdelivr.net/npm/photoswipe@4.1.3/dist/photoswipe.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/photoswipe@4.1.3/dist/photoswipe-ui-default.min.js"></script>

<script>
    function viewer_init() {
        let pswpElement = document.querySelectorAll('.pswp')[0];
        let $imgArr = document.querySelectorAll(('.article-entry img:not(.reward-img)'))

        $imgArr.forEach(($em, i) => {
            $em.onclick = () => {
                // slider展开状态
                // todo: 这样不好，后面改成状态
                if (document.querySelector('.left-col.show')) return
                let items = []
                $imgArr.forEach(($em2, i2) => {
                    let img = $em2.getAttribute('data-idx', i2)
                    let src = $em2.getAttribute('data-target') || $em2.getAttribute('src')
                    let title = $em2.getAttribute('alt')
                    // 获得原图尺寸
                    const image = new Image()
                    image.src = src
                    items.push({
                        src: src,
                        w: image.width || $em2.width,
                        h: image.height || $em2.height,
                        title: title
                    })
                })
                var gallery = new PhotoSwipe(pswpElement, PhotoSwipeUI_Default, items, {
                    index: parseInt(i)
                });
                gallery.init()
            }
        })
    }
    viewer_init()
</script>



<script type="text/x-mathjax-config">
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      tex2jax: {
          inlineMath: [ ['$','$'], ["\\(","\\)"]  ],
          processEscapes: true,
          skipTags: ['script', 'noscript', 'style', 'textarea', 'pre', 'code']
      }
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  MathJax.Hub.Queue(function() {
      var all = MathJax.Hub.getAllJax(), i;
      for(i=0; i < all.length; i += 1) {
          all[i].SourceElement().parentNode.className += ' has-jax';
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<script src="https://cdn.jsdelivr.net/npm/mathjax@2.7.6/unpacked/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>


<script type="text/javascript" src="https://js.users.51.la/20544303.js"></script>
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